“Can we position it with a fluid?”

Hydraulics and pneumatics both use fluids to manipulate, propel or position. Hydraulics rely on liquids which resist compression while pneumatics rely on gases which permit compression.

Both hydraulic and pneumatic systems can work through flexible tubing, allowing them to apply force to moving parts.


Hydraulics have a valuable force multiplier effect, making them useful for powerful machines like bulldozers and automotive braking systems.


Air tents and inflatable rafts inflate from a small portable size. The inflatable raft also floats even as it takes on water.

A bouncy castle is also portable and thanks to the compressibility of air, is a safe, yielding platform for children to play in. This same yielding nature makes pneumatic tires ideal for automotive applications as they provide a smoother ride.

Bubble wrap is light weight and protective.

More examples

As I stumble across real world examples of this Inventive Principle in action I add them here.

Your turn

What problems do you face that this inventive principle could help solve? Have you used this principle before?